You can enter can't serve times for an entire family at one time by opening up the family and adding the can't serve time in the Edit Family dialog, as opposed to adding the can't serve time to the profile of an individual volunteer within the family.
- Click on the Family Groupings pane
- Open up the family to which you'd like to add the can't serve time
- Add the time
- Click OK to close the Edit Family dialog
The can't serve time will now apply to and be visible in each family members' profile.